Meaning of << operator in C -

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this question has answer here:

i wondering know meaning of operator << in 

#define  x (10 * (1<<12));

it's bitshift operator. << shift left, >> shift right. 1 << 12 means shift value (the int '1') 12 bits left.

'1' 00000000 00000000 00000000 00000001 in binary, if it's 32 bit integer. shift left 12 places, changes to: 00000000 00000000 00010000 00000000

if shift 5 << 8, '5' 101 in binary, it'll shift:

00000000 00000000 00000000 00000101

into:

00000000 00000000 00000101 00000000

see this question details on other bitwise operators.


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